I used I" w/ 45 degree angles up and down no 90 degree. I am starting with a 1900gph waterfall pump I got at tractor supply when I got my Stock tub. If its too much I will probably use my current one which is 1200gph but I have ball valves I can use too. I also put a check valve running from pump in case power goes out. Here is a pic of just the sump in the water to clear it up before I put the slimmer in the bucket. Getting my chaeto tomorrow.
